US20140148343A1 - Re123-based superconducting wire and method of manufacturing the same - Google Patents
Re123-based superconducting wire and method of manufacturing the same Download PDFInfo
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Images
Classifications
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B12/00—Superconductive or hyperconductive conductors, cables, or transmission lines
- H01B12/02—Superconductive or hyperconductive conductors, cables, or transmission lines characterised by their form
- H01B12/04—Single wire
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G1/00—Methods of preparing compounds of metals not covered by subclasses C01B, C01C, C01D, or C01F, in general
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G27/00—Compounds of hafnium
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G3/00—Compounds of copper
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B12/00—Superconductive or hyperconductive conductors, cables, or transmission lines
- H01B12/02—Superconductive or hyperconductive conductors, cables, or transmission lines characterised by their form
- H01B12/06—Films or wires on bases or cores
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
- H10N60/01—Manufacture or treatment
- H10N60/0268—Manufacture or treatment of devices comprising copper oxide
- H10N60/0296—Processes for depositing or forming copper oxide superconductor layers
- H10N60/0521—Processes for depositing or forming copper oxide superconductor layers by pulsed laser deposition, e.g. laser sputtering
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
- H10N60/01—Manufacture or treatment
- H10N60/0268—Manufacture or treatment of devices comprising copper oxide
- H10N60/0828—Introducing flux pinning centres
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
- H10N60/80—Constructional details
- H10N60/85—Superconducting active materials
- H10N60/855—Ceramic superconductors
- H10N60/857—Ceramic superconductors comprising copper oxide
Definitions
- the present invention relates to an RE123-based superconducting wire including artificial pinning centers introduced into a superconducting layer and a method of manufacturing the same.
- An RE123-based oxide superconductor has a composition represented by RE 1 Ba 2 Cu 3 O 7 ⁇ (RE: rare earth element such as Y or Gd).
- RE rare earth element such as Y or Gd
- the RE123-based oxide superconductor has a higher critical temperature than the temperature of liquid nitrogen (77 K), and the application to superconducting equipment such as superconducting devices, transformers, current-limiting devices, motors and magnets is to be expected.
- a superconductor formed to have favorable crystal orientation using an RE123-based oxide superconductor exhibits strong critical current characteristics in a self-magnetic field.
- a magnetic field is applied to a superconductor in a superconducting state so as to make a current flow
- a Lorentz force is generated in a quantized magnetic flux which has intruded into the superconductor.
- the quantized magnetic flux is moved due to the Lorentz force, a voltage is generated in a current direction, and a resistance is generated. Since the Lorentz force increases as the current value increases and the magnetic field intensifies, the critical current characteristics degrade when an external magnetic field becomes strong.
- a method in which a nanoscale foreign phase (a different phase from the superconducting layer), such as an impurity or a defect, is incorporated into the superconducting layer so as to pin the magnetic flux, thereby improving the critical current characteristics in the magnetic field of the superconductor.
- a method in which a normal conductor of a composite oxide including Ba, such as BaZrO 3 , is introduced into a superconducting layer including an RE123-based oxide superconductor as an artificial pinning center (in the present specification, also referred to as magnetic flux pinning point or pinning point) (for example, refer to U.S. Pat. No. 7,737,087 and PCT International Publication No. WO 2009/044637).
- FIG. 12 is a graph illustrating the characteristics changes of the critical current density J c with respect to an external magnetic field ⁇ G H depending on the introduction of BaZrO 3 into an YBa 2 Cu 3 O 7 ⁇ (YBCO) superconducting layer described in U.S. Pat. No. 7,737,087.
- YBCO YBCO
- FIG. 12 when BaZrO 3 artificial pinning centers are introduced into the YBCO superconducting layer, it is possible to improve the critical current density in the magnetic field (for example, the critical current density improves in a 3T magnetic field from approximately 0.1 MA/cm 2 to approximately 0.2 MA/cm 2 ) compared to when no artificial pinning centers are introduced.
- FIG. 13 illustrates a graph plotting a relationship between the film thickness of a GdBa 2 Cu 3 O 7 ⁇ (GdBCO) superconducting layer and the minimum critical current value (I cmin ) in an RE123-based superconducting wire manufactured using the PLD method.
- GdBCO GdBa 2 Cu 3 O 7 ⁇
- the present invention has been made in consideration of the above circumstances of the related art, and provides an RE123-based superconducting wire which can suppress a decrease in a critical current in a magnetic field and has favorable critical current characteristics even when the film thickness of a superconducting layer exceeds 1 ⁇ m, and a method of manufacturing the same.
- An aspect of a present RE123-based superconducting wire including a base material, an intermediate layer formed on the base material, and an oxide superconducting layer which is formed on the intermediate layer and includes an oxide superconductor represented by a composition formula of RE 1 Ba 2 Cu 3 O 7 ⁇ (RE represents one or two or more rare earth elements), in which the oxide superconducting layer includes 0.5 to 10 mol % of a Hf-including compound dispersed in the oxide superconducting layer as an artificial pinning center, a film thickness d of the oxide superconducting layer is d>1 ⁇ m, and a current characteristic of J cd /J c1 ⁇ 0.9 (J c1 represents a critical current density when the thickness of the oxide superconducting layer is 1 ⁇ m, and J cd represents the critical current density when the thickness of the oxide superconducting layer is d ⁇ m) is satisfied.
- RE represents one or two or more rare earth elements
- the Hf-including compound functions as an artificial pinning center (hereinafter, also referred to as magnetic flux pinning point or pinning point), and the degradation of the critical current characteristics in a magnetic field can be suppressed even when the film thickness of the oxide superconducting layer exceeds 1 ⁇ m.
- the Hf-including compound is preferably MHfO 3 (M represents Ba, Sr or Ca).
- RE is preferably one or two or more of Gd, Y and Sm.
- M is preferably Ba.
- the Hf-including compound which has been introduced into the oxide superconducting layer effectively functions as an artificial pinning center due to the addition of BaHfO 3 , and an effect that suppresses the degradation of the critical current characteristics through the application of an external magnetic field further improves.
- 1.5 to 7.5 mol % or 1.5 to 5.0 mol % of a hafnium composite oxide MHfO 3 (M represents Ba, Sr or Ca) is also preferably dispersed in the oxide superconducting layer.
- One aspect of a present method of manufacturing an RE123-based superconducting wire includes, dispersing a Hf-including compound as an artificial pinning center on an intermediate layer formed on a base material using a physical vapor deposition method in which a target is used, adding 0.5 to 10 mol % of a Hf oxide to an oxide superconductor having a composition formula represented by RE 1 Ba 2 Cu 3 O 7 ⁇ (RE represents one or two or more rare earth elements) or powder of the oxide superconductor in the target, and forming the oxide superconducting layer which satisfies a current characteristic of J cd /J c1 ⁇ 0.9 (J c1 represents a critical current density when the thickness of the oxide superconducting layer is 1 ⁇ m, and J cd represents the critical current density when the thickness of the oxide superconducting layer is d ⁇ m) and which has a film thickness d of d>1 ⁇ m.
- RE represents one or two or more rare earth elements
- an oxide superconducting wire may be formed on the intermediate layer formed on the base material using the pulsed laser deposition method while moving the base material.
- FIG. 1 is a schematic configuration view illustrating an embodiment of an RE123-based superconducting wire according to the present invention.
- FIG. 2 is a schematic view illustrating an example of a film-forming apparatus being used in a method of manufacturing a superconductor in the RE123-based superconducting wire according to the present invention.
- FIG. 3 is a graph illustrating the characteristics of the critical current densities of RE123-based superconducting wires of Example 1 and Comparative Examples 1 to 3.
- FIG. 4 is a graph illustrating the dependencies of the critical current densities of RE123-based superconducting wires of Example 1 and Comparative Examples 1 to 3 on magnetic field applied angles.
- FIG. 5A is a TEM photograph of a cross sectional image of an oxide superconducting layer in the RE123-based superconducting wire of Example 1.
- FIG. 5B illustrates TEM photographs of cross sectional images of oxide superconducting layers in the RE123-based superconducting wires of Example 1 and Comparative Examples 2 and 3.
- FIG. 6A is an electron diffraction pattern of the oxide superconducting layer in the RE123-based superconducting wire of Example 1.
- FIG. 6B is an electron diffraction pattern of the oxide superconducting layer in the RE123-based superconducting wire of Comparative Example 2.
- FIG. 6C is an electron diffraction pattern of the oxide superconducting layer in the RE123-based superconducting wire of Comparative Example 3.
- FIG. 7 is a graph illustrating the dependencies of the critical current densities of RE123-based superconducting wires of Examples 2 and 3 and Comparative Examples 4 and 5 on magnetic field applied angles.
- FIG. 8 is a graph illustrating the critical current characteristics of RE123-based superconducting wires of Example 4 and Comparative Examples 6 and 7.
- FIG. 9 is a graph plotting J cd /J c1 with respect to the film thicknesses of the oxide superconducting layers in the RE123-based superconducting wires of Example 4 and Comparative Examples 6 to 8.
- FIG. 10A is a graph illustrating the critical current characteristics of superconducting wires of Examples 5 and 6 and Comparative Examples 9 and 10 depending on magnetization rates at 77 K and in a range of 0T to 5T.
- FIG. 10B is a graph illustrating the critical current characteristics of the same superconducting wires depending on magnetization rates at 65K and in a range of 0T to 5T.
- FIG. 10C is a graph illustrating the critical current characteristics of the same superconducting wires depending on magnetization rates at 40K and in a range of 0T to 5T.
- FIG. 10D is a graph illustrating the critical current characteristics of the same superconducting wires depending on magnetization rates at 20K and in a range of 0T to 5T.
- FIG. 11 is a graph illustrating the critical current characteristics of superconducting wires manufactured in examination examples.
- FIG. 12 is a graph illustrating the characteristic changes of the critical current density with respect to an external magnetic field depending on the introduction of BaZrO 3 into an YBa 2 Cu 3 O 7 ⁇ superconducting layer.
- FIG. 13 is a graph plotting a relationship between the film thickness of a GdBa 2 Cu 3 O 7 ⁇ superconducting layer and the minimum critical current value in an RE123-based superconducting wire manufactured using a PLD method.
- FIG. 1 is a schematic configuration view illustrating the embodiment of the RE123-based superconducting wire according to the present invention.
- An RE123-based superconducting wire 10 illustrated in FIG. 1 includes a long base material 11 , an intermediate layer 12 formed on the base material 11 , a cap layer 13 formed on the intermediate layer 12 , an oxide superconducting layer 14 formed on the cap layer 13 , and a stabilizing layer 15 formed on the oxide superconducting layer 14 .
- a tape-shaped, plate-shaped or rectangular metallic material can be used as the base material 11 .
- metal such as Cu, Ni, Ti, Mo, Nb, Ta, W, Mn, Fe or Ag or an alloy thereof which is excellent in terms of strength and heat resistance can be used.
- the material is preferably stainless steel, HASTELLOY (registered trademark), or a nickel-based alloy due to its excellent corrosion resistance and excellent heat resistance.
- an oriented metal substrate such as an oriented Ni—W substrate obtained by introducing a texture into a nickel alloy or the like may be used as the base material 11 .
- the base material 11 can be set in a range of approximately 0.01 to 0.5 mm in thickness in order to be used for an oxide superconducting wire.
- the intermediate layer 12 is a thin film formed using an ion beam assist deposition method (IBAD method).
- IBAD method ion beam assist deposition method
- MgO, GZO (Gd 2 Zr 2 O 7 ), YSZ (yttria-stabilized zirconia), SrTiO 3 or the like can be used.
- a material having a smaller value of the half width (full width at half maximum, FWHM) ⁇ of crystal axis dispersion in an in-plane direction, which is an index that indicates the degree of crystalline orientation, that is, a material which can have a favorable degree of in-plane crystalline orientation is preferably selected.
- a film-forming method such as a sputtering method, an electron beam deposition method or a PLD method may be used as well as the IBAD method.
- the thickness of the intermediate layer 12 is preferably, for example, in a range of 1 nm to 1.0 ⁇ m.
- a diffusion prevention layer may be formed between the base material 11 and the intermediate layer 12 in order to prevent the diffusion of elements during a heating treatment.
- the diffusion prevention layer is highly thermal-resistant, is provided to reduce the interface reactivity, and has a function of providing favorable orientation to the thin film-shaped intermediate layer 12 disposed on the diffusion prevention layer.
- the diffusion prevention layer may be disposed as necessary, and a material therefor may be, for example, GZO (Gd 2 Zr 2 O 7 ), yttria (Y 2 O 3 ), silicon nitride (Si 3 N 4 ), aluminum oxide (Al 2 O 3 , “alumina”) or the like.
- the diffusion prevention layer is formed in a thickness in a range of several tens of nanometers to 200 nm using, for example, a sputtering method. One diffusion prevention layer or two diffusion prevention layers may be formed.
- the cap layer 13 has a function of controlling the orientation of the oxide superconducting layer 14 formed on the cap layer, a function of suppressing the diffusion of elements that form the oxide superconducting layer 14 into other layers, and the like.
- the cap layer 13 provides a higher degree of in-plane orientation than the intermediate layer 12 .
- a material for the cap layer 13 include CeO 2 , LMO (LaMnO 3 ), SrTiO 3 , Y 2 O 3 , Al 2 O 3 and the like.
- the appropriate film thickness of the cap layer 13 differs depending on the material.
- the film thickness may be in a range of 50 nm to 1 ⁇ m.
- the PLD method, the sputtering method or the like can be used to form the cap layer 13 , and the PLD method is desirably used since a large film-forming rate can be obtained.
- the oxide superconducting layer 14 is formed of an RE123-based oxide superconductor.
- a Hf-including compound is added to the oxide superconducting layer 14 so that a foreign phase including Hf is dispersed.
- the RE123-based oxide superconductor is a substance having a composition formula represented by RE 1 Ba 2 Cu 3 O 7 ⁇ (RE represents one or two or more rare earth elements, and 6.5 ⁇ 7 ⁇ 7 ⁇ 7.1 is satisfied), and RE is preferably one or two or more of Gd, Y and Sm.
- RE represents one or two or more rare earth elements, and 6.5 ⁇ 7 ⁇ 7 ⁇ 7.1 is satisfied
- RE is preferably one or two or more of Gd, Y and Sm.
- the foreign phase being dispersed in the oxide superconducting layer 14 includes Hf, serves as a normal conduction portion, and functions as an artificial pinning center (magnetic flux pinning point) that controls the movement of a quantized magnetic flux in the oxide superconducting layer 14 .
- the foreign phase including Hf which serves as an artificial pinning center, is formed by adding a Hf-including compound to the RE123-based oxide superconductor when forming the oxide superconducting layer 14 .
- the Hf-including compound is preferably a hafnium composite oxide MHfO 3 (M represents Ba, Sr or Ca) or a hafnium oxide HfO 2 , and specific examples thereof include BaHfO 3 , SrHfO 3 and CaHfO 3 .
- M represents Ba, Sr or Ca
- BaHfO 3 is particularly preferable since BaHfO 3 effectively functions as a pinning point and has a strong effect that suppresses the degradation of the critical current characteristics by the application of an external magnetic field.
- the proportion of the Hf-including compound being added to the oxide superconducting layer 14 is in a range of 0.5 to 10 mol %, preferably in a range of 1.5 to 7.5 mol %, and more preferably in a range of 1.5 to 5.0 mol %.
- the proportion of the foreign phase (artificial pinning center) including Hf which is introduced into the oxide superconducting layer 14 , also becomes the same as the proportion of the Hf-including compound.
- the foreign phase including Hf effectively suppresses the movement of a quantized magnetic flux, suppresses a decrease in the critical current in a magnetic field, and enables the obtainment of an RE123-based superconducting wire having favorable critical current characteristics.
- the proportion of the Hf-including compound being added to the oxide superconducting layer 14 is less than the lower limit value, there is a probability that it may become difficult to obtain the pinning effect of the foreign phase including Hf which is dispersed as an artificial pinning center.
- the foreign phase in the oxide superconducting layer 14 can be identified using an X-ray diffraction (XRD) method or an electron diffraction method.
- XRD X-ray diffraction
- the ratio of the composition of the oxide superconducting layer 14 can be specified using, for example, an ICP atomic emission spectrometry.
- the shape or rod diameter of the foreign phase in the oxide superconducting layer 14 can be specified by observing a cross sectional image using a transmission electron microscope (TEM).
- the foreign phase including Hf which is dispersed in the oxide superconducting layer 14 as a magnetic flux pinning point (artificial pinning center), is a hafnium composite oxide MHfO 3 (M represents Ba, Sr or Ca), HfO 2 or the like, and specific examples thereof include BaHfO 3 , SrHfO 3 , CaHfO 3 , HfO 2 and the like.
- M represents Ba, Sr or Ca
- HfO 2 or the like
- specific examples thereof include BaHfO 3 , SrHfO 3 , CaHfO 3 , HfO 2 and the like.
- the Hf-including compound which is added to the oxide superconducting layer 14 is BaHfO 3
- the artificial pinning center which is the foreign phase including Hf is BaHfO 3 , HfO 2 or the like.
- the foreign phase including Hf in the oxide superconducting layer 14 is mainly BaHfO 3 .
- the proportion of the foreign phase including Hf which is dispersed in the oxide superconducting layer 14 as an artificial pinning center, becomes substantially the same as the proportion of the Hf-including compound which has been added to the oxide superconducting layer 14 . Therefore, the proportion of the foreign phase including Hf in the oxide superconducting layer 14 is, similarly to the addition amount of the Hf-including compound, preferably in a range of 0.5 to 10 mol %, more preferably in a range of 1.5 to 7.5 mol %, and still more preferably in a range of 1.5 to 5.0 mol %.
- the thickness d of the oxide superconducting layer 14 is larger than 1 ⁇ m, preferably in a range of 1 to 10 ⁇ m, and more preferably in a range of 1 to 5 ⁇ m. In addition, the thickness of the oxide superconducting layer 14 is preferably uniform.
- a Hf-including compound is added to the oxide superconducting layer 14 so as to disperse a foreign phase including Hf in the oxide superconducting layer 14 .
- the foreign phase including Hf functions as a pinning point (magnetic flux pinning point) so that the RE123-based superconducting wire exhibits a current characteristic of J cd /J c1 ⁇ 0.9 even when the thickness d of the oxide superconducting layer 14 is larger than 1 ⁇ m.
- J c1 represents the critical current density when the thickness of the oxide superconducting layer 14 is 1 ⁇ m
- J cd represents the critical current density when the thickness of the oxide superconducting layer 14 is d ⁇ m.
- J cd /J c1 ⁇ 0.9 indicates that critical current density J cd when the thickness of the oxide superconducting layer 14 is d ⁇ m is 90% or more of the value of the critical current density J c1 when the thickness of the oxide superconducting layer 14 is 1 ⁇ m. Therefore, in the RE123-based superconducting wire 10 of the embodiment, a decrease in the critical current density can be suppressed even when the film thickness of the oxide superconducting layer 14 increases from 1 to d ⁇ m.
- the critical current density does not easily decrease even when the film thickness of the oxide superconducting layer 14 increases, in examples described below, as illustrated in FIG. 8 , there is a tendency that the critical current value linearly increases in proportion to an increase in the film thickness in the superconducting wire 10 of the embodiment in which BaHfO 3 (BHO) is added to the oxide superconducting layer 14 .
- the oxide superconducting layer 14 can be stacked using a physical vapor deposition method such as a sputtering method, a vacuum deposition method, a laser deposition method or an electron-beam deposition method; a chemical vapor deposition method (CVD method); a metal organic deposition method (MOD method); or the like.
- a physical vapor deposition method such as a sputtering method, a vacuum deposition method, a laser deposition method or an electron-beam deposition method; a chemical vapor deposition method (CVD method); a metal organic deposition method (MOD method); or the like.
- a pulsed laser deposition method PLD method
- TFA-MOD method a metal organic deposition method of organic metal using trifluoroacetate
- CVD method a metal organic deposition method
- the MOD method refers to a method of applying and then thermally decomposing a salt of an organic acid of metal in which a solution obtained by uniformly dissolving an organic compound of a metal component is applied to a base material and then heated so as to be thermally decomposed, thereby forming a thin film on the base material. Since no vacuum process is required and a film can be formed at a high speed and a low cost, the MOD method is suitable for the manufacturing of oxide superconductors having a long tape shape. In addition, the introduction proportion of the foreign phase including Hf in the oxide superconducting layer 14 being formed can be controlled by adjusting the composition of a raw material solution.
- the introduction proportion of the foreign phase including Hf in the oxide superconducting layer 14 being formed can be controlled by controlling the type and flow rate of a source material gas.
- the introduction proportion of the foreign phase including Hf in the oxide superconducting layer 14 being formed can be controlled by adjusting the composition ratio of a target being used.
- the composition ratio of a raw material is adjusted so that the Hf-including compound is incorporated into the RE123-based oxide superconductor represented by a composition formula of RE 1 Ba 2 Cu 3 O 7 ⁇ in a range of 0.5 to 10 mol %, preferably in a range of 1.5 to 7.5 mol %, and more preferably in a range of 1.5 to 5.0 mol %. Then, a thin film in which the above composition ratio is reflected (oxide superconducting layer 14 ) can be formed.
- a powder-form Hf-including compound such as a hafnium composite oxide MHfO 3
- a powder-form RE123-based oxide superconductor represented by a composition formula of RE 1 Ba 2 Cu 3 O 7 ⁇ or powder including the constitution elements of the RE123-based oxide superconductor
- a hafnium composite oxide MHfO 3 for example, HfO 2 or the like
- the oxide superconducting layer 14 is particularly preferable to form the oxide superconducting layer 14 using the PLD method.
- the formation of the oxide superconducting layer 14 using the PLD method will be described.
- FIG. 2 is a schematic perspective view illustrating an example of a laser deposition apparatus being used to form the oxide superconducting layer 14 using the PLD method.
- the oxide superconducting layer 14 can be formed using the laser deposition apparatus illustrated in FIG. 2 after the diffusion prevention layer or the intermediate layer 12 and the cap layer 13 are previously formed on the base material 11 using the film-forming method described above.
- the laser deposition apparatus illustrated in FIG. 2 includes a reduced-pressure container connected to a pressure-reducing apparatus such as a vacuum pump and can radiate a laser beam B on a target 20 installed in the reduced-pressure container from a laser beam radiation apparatus installed outside the reduced-pressure container.
- a supply reel 21 , a winding reel 22 and a sheet-like heating apparatus 23 in the middle location between the supply reel and the winding reel are installed in the reduced-pressure container.
- the tape-shaped base material 11 can be moved from the supply reel 21 to the winding reel 22 through the heating apparatus 23 . Particles sputtered or evaporated from the target 20 due to the laser beam B are deposited on the base material 11 that is heated to a desired film-forming temperature in the heating apparatus 23 while being moved, thereby forming a film.
- the target 20 is made of a sheet material such as a sintered body in which a Hf-including compound such as MHfO 3 is incorporated into a composite oxide or an RE123-based oxide superconductor which has an identical or similar composition to the oxide superconducting layer 14 to be formed or includes a large amount of components that are easily removed during the formation of a film at a desired proportion.
- a Hf-including compound such as MHfO 3
- RE123-based oxide superconductor which has an identical or similar composition to the oxide superconducting layer 14 to be formed or includes a large amount of components that are easily removed during the formation of a film at a desired proportion.
- the laser deposition apparatus illustrated in FIG. 2 forms a film while transporting the base material 11 in the longitudinal direction at a transportation speed in a range of, for example, 2 to 200 m/h and heating the base material 11 to a preferable temperature (for example, 700 to 1000° C.) as the film-forming temperature of the oxide superconducting layer 14 .
- a preferable temperature for example, 700 to 1000° C.
- a plume F 1 of deposition particles sputtered or evaporated from the target 20 is disposed on the surface of the cap layer 13 on the base material 11 passing the region opposite to the target 20 , and therefore the oxide superconducting layer 14 is formed.
- the oxide superconducting layer 14 having a large film thickness is formed using the PLD method while transporting the base material, a decrease in the critical current due to an increase in the film thickness of the oxide superconducting layer 14 can be suppressed as illustrated in FIG. 8 and excellent critical current characteristics are exhibited.
- the stabilizing layer 15 is preferably stacked on the oxide superconducting layer 14 as illustrated in FIG. 1 .
- the stabilizing layer 15 stacked on the oxide superconducting layer 14 is a principle component that functions as a current bypass route, in which a current flowing in the oxide superconducting layer 14 is commutated when some regions of the oxide superconducting layer 14 are about to turn into a normal conduction state, so as to stabilize the oxide superconducting layer 14 and prevent burnout.
- the stabilizing layer 15 is preferably formed of a metal having favorable conductivity, and specific examples thereof include silver, silver alloys, copper and the like.
- a single layer of the stabilizing layer 15 may be provided, or the stabilizing layer may be provided in a laminate structure of two or more layers.
- the stabilizing layer 15 can be stacked using a well-known method, and it is possible to form a silver layer using plating or a sputtering method and to attach a copper tape or the like on the silver layer.
- the thickness of the stabilizing layer 15 may be in a range of 0.1 to 300 ⁇ m.
- the RE123-based superconducting wire 10 of the embodiment 0.5 to 10 mol % of a Hf-including compound is added to the oxide superconducting layer 14 so as to disperse the foreign phase including Hf in the oxide superconducting layer 14 .
- the foreign phase including Hf functions as a pinning point and can suppress the degradation of the critical current characteristics in a magnetic field even when the film thickness of the oxide superconducting layer 14 is d>1 ⁇ m.
- a number of nanosized (rod diameter of approximately 5 nm) columnar crystals (nanorods) formed by adding MHfO 3 to the oxide superconducting layer are precipitated and dispersed in the RE123-based superconducting wire 10 of the embodiment, in which 0.5 to 10 mol % of the hafnium composite oxide MHfO 3 is added to the oxide superconducting layer 14 , as illustrated in FIG. 4 described below. Therefore, compared with a superconducting wire into which a BaZrO 3 artificial pinning centers are introduced, the nanorods are assumed to function as pinning points for magnetic fluxes at all angles (directions), and therefore it becomes possible to improve the critical current characteristics at all domains of magnetic field applied angles.
- the RE123-based superconducting wire of the present invention According to the method of manufacturing the RE123-based superconducting wire of the present invention described above, it is possible to provide the RE123-based superconducting wire 10 that can suppress the degradation of the critical current characteristics in a magnetic field even when the film thickness of the oxide superconducting layer 14 exceeds 1 ⁇ m.
- the following base material will be used as a base material for superconducting wires.
- a 110 nm-thick Gd 2 Zr 2 O 7 (GZO) layer is formed on a HASTELLOY (registered trademark) C276 (trade name of Haynes International Inc.) base material having a width of 10 mm, a thickness of 0.1 mm and a length of approximately 10 cm using the sputtering method, and, furthermore, a 3 nm-thick MgO layer is formed on the GZO layer using the IBAD method, thereby forming an intermediate layer.
- HASTELLOY registered trademark
- C276 trade name of Haynes International Inc.
- LMO LaMnO 3
- An RE123-based oxide superconducting layer having a film thickness of 1.0 ⁇ m is formed on the Ce 2 O layer of the base material for superconducting wires manufactured as described above in the following order using the laser deposition apparatus illustrated in FIG. 2 .
- a long metallic base material is wound around the supply reel in the laser deposition apparatus illustrated in FIG. 2 as a dummy base material. An end portion of the long metallic base material is pulled out, fixed to the winding reel, and installed so that the long metallic base material can be transported in the longitudinal direction from the supply reel to the winding reel.
- the base material for superconducting wires manufactured as described above is connected to a supply reel side of the long metallic base material, which is the dummy base material installed between the pair of reels, in a manner that a film is to be formed on the CeO 2 layer.
- the supply reel and the winding reel are driven in synchronization with each other so as to transport the long metallic base material in the longitudinal direction and to transport the base material for superconducting wires which is fixed to the long metallic base material from the supply reel to the winding reel.
- An RE123-based oxide superconducting layer having a film thickness of 1.6 ⁇ m is formed on the CeO 2 layer while the base material for superconducting wires passes through a film-forming region opposite to a target.
- a target obtained by sintering powder manufactured by incorporating 1.5 mol % of BaHfO 3 into powder of GdBa 2 Cu 3 O 7 ⁇ is used in the formation of the oxide superconducting layer.
- the film-forming conditions are a temperature of a heating apparatus (heater) of 1070° C., a pressure of 80 Pa, a laser output of 34 W, in an atmosphere with 100% oxygen, and a transportation speed of the base material for superconducting wires of 20 m/h.
- the base material is made to pass through the film-forming region multiple times under such conditions with the repetitive change of transportation directions of the base material.
- a 5 ⁇ m-thick Ag layer (stabilizing layer) is sputtered on the oxide superconducting layer, thereby manufacturing an RE123-based superconducting wire.
- oxide superconducting layers are formed under the same conditions as above except that the incorporation amount of BaHfO 3 into the target is changed to 2.5 mol %, 3.5 mol %, 5 mol % and 7 mol %, thereby manufacturing RE123-based superconducting wires.
- RE123-based superconducting wires are manufactured in the same manner as in Example 1 except that the oxide superconducting layer is formed using a sintered body of GdBa 2 Cu 3 O 7 ⁇ as the target.
- RE123-based superconducting wires are manufactured in the same manner as in Example 1 except that the oxide superconducting layer is formed using a sintered body obtained by sintering powder of GdBa 2 Cu 3 O 7 ⁇ into which 3.5 mol %, 5 mol % or 7.5 mol % of BaZrO 3 has been incorporated as the target.
- RE123-based superconducting wires are manufactured in the same manner as in Example 1 except that the oxide superconducting layer is formed using a sintered body obtained by sintering powder of GdBa 2 Cu 3 O 7 ⁇ into which 3.5 mol %, 5 mol %, 7.5 mol % or 10 mol % of BaSnO 3 has been incorporated as the target.
- FIG. 3 illustrates the results in which the minimum values J cmin of the critical current densities of the respective RE123-based superconducting wires are plotted. Meanwhile, in FIG. 3 , “BHO” indicates the results of Example 1, “PURE” indicates the results of Comparative Example 1, “BZO” indicates the results of Comparative Example 2, and “BSO” indicates the results of Comparative Example 3.
- FIG. 3 show that the critical current density in a 3T magnetic field significantly improves in the RE123-based superconducting wire of Example 1 in which BaHfO 3 is added to an RE123-based oxide superconductor so as to introduce artificial pinning centers compared with the superconducting wire of Comparative Example 1 into which no artificial pinning centers have been introduced.
- the effect that improves the critical current characteristics of the superconducting wire into which the artificial pinning centers have been introduced by adding BaHfO 3 is stronger than the effect of the introduction of the artificial pinning centers through the addition of BaSnO 3 when the addition amount is in a range of 1.5 to 5 mol %, and is much stronger than the effect of the introduction of the artificial pinning centers through the addition of BaZrO 3 when the addition amount is in a range of 1.5 to 7.5 mol %.
- FIG. 4 illustrates the results in which the dependencies of the critical current densities of the respective superconducting wires on magnetic field applied angles are plotted.
- the minimum value of the critical current density of the superconducting wire of Example 1 at 77 K in a 3T magnetic field, which is indicated by “BHO 3.5 mol %” in FIG. 4 is 0.33 MA/cm 2 .
- the minimum values of “PURE”, “BZO 5 mol %” and “BSO 7.5 mol %” are 0.14 MA/cm 2 , 0.28 MA/cm 2 and 0.33 MA/cm 2 , respectively.
- the superconducting wires of Example 1 can suppress the degradation of the critical current characteristics in a wider range of magnetic field applied angles than the superconducting wires of Comparative Examples 1 to 3. Therefore, in Example 1, compared to Comparative Examples 1 to 3, the nanorods are assumed to function as pinning points for magnetic fluxes at all angles (directions), and therefore it becomes possible to improve the critical current characteristics at all domains of magnetic field applied angles.
- FIG. 5A illustrates the results of transmission electron microscope (TEM) observation of a cross sectional image of the oxide superconducting layer in the superconducting wire to which 5 mol % of BaHfO 3 (BHO) has been added among the RE123-based superconducting wires of Example 1.
- TEM transmission electron microscope
- a number of columnar crystals (nanorods) having a rod diameter of approximately 5 nm are dispersed in the oxide superconducting layer as pinning points.
- FIG. 5B illustrates the results of transmission electron microscope (TEM) observation of cross sectional images of the oxide superconducting layers in the RE123-based superconducting wires of Example 1 and Comparative Examples 2 and 3.
- TEM transmission electron microscope
- Example 1 having the smallest addition amount, a larger number of nanorods having a small diameter are dispersed than in Comparative Examples 2 and 3. Therefore, when the RE123-based superconducting wire of Example 1 is used, it is possible to effectively improve the critical current density in a magnetic field.
- the oxide superconducting layers are analyzed using the electron diffraction method and the ICP atomic emission spectrometry.
- the obtained electron diffraction patterns are illustrated in FIGS. 6A to 6C respectively.
- Example 1 in the oxide superconducting layers in the superconducting wires of Example 1, BaHfO 3 crystals are dispersed in GdBa 2 Cu 3 O 7 ⁇ (GdBCO) crystals.
- RE123-based superconducting wires are manufactured in the same order and conditions as in Example 1 except that a target obtained by sintering powder manufactured by incorporating 3.5 mol % of BaHfO 3 (BHO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 1.2 ⁇ m.
- a target obtained by sintering powder manufactured by incorporating 3.5 mol % of BaHfO 3 (BHO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 1.2 ⁇ m.
- RE123-based superconducting wires are manufactured in the same order and conditions as in Example 1 except that a target obtained by sintering powder manufactured by incorporating 3.5 mol % of BaHfO 3 (BHO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 2.2 ⁇ m.
- a target obtained by sintering powder manufactured by incorporating 3.5 mol % of BaHfO 3 (BHO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 2.2 ⁇ m.
- RE123-based superconducting wires are manufactured in the same order and conditions as in Comparative Example 2 except that a target obtained by sintering powder manufactured by incorporating 5 mol % of BaZrO 3 (BZO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 1.1 ⁇ m.
- a target obtained by sintering powder manufactured by incorporating 5 mol % of BaZrO 3 (BZO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 1.1 ⁇ m.
- RE123-based superconducting wires are manufactured in the same order and conditions as in Comparative Example 2 except that a target obtained by sintering powder manufactured by incorporating 5 mol % of BaZrO 3 (BZO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 2.1 ⁇ m.
- a target obtained by sintering powder manufactured by incorporating 5 mol % of BaZrO 3 (BZO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 2.1 ⁇ m.
- FIG. 7 illustrates the results in which the dependencies of the critical current densities of the superconducting wires on magnetic field applied angles are plotted.
- “BHO 1.2 ⁇ m” represents the results of Example 2
- “BHO 2.2 ⁇ m” represents the results of Example 3
- “BZO 1.1 ⁇ m” represents the results of Comparative Example 4
- “BZO 2.1 ⁇ m” represents the results of Comparative Example 5.
- the characteristic change in the critical current density is small even when the film thickness of the oxide superconducting layer is increased from 1.2 to 2.2 ⁇ m. That is, a decrease in the critical current density due to the increase in the film thickness is successfully suppressed.
- a plurality of RE123-based superconducting wires in which the film thickness of the oxide superconducting layer has been changed in a range of 1.1 to 2.9 ⁇ m are manufactured in the same order and conditions as in Example 1 except that a target obtained by sintering powder manufactured by incorporating 3.5 mol % of BaHfO 3 (BHO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used.
- BHO BaHfO 3
- a plurality of RE123-based superconducting wires in which the film thickness of the oxide superconducting layer has been changed in a range of 0.9 to 3.2 ⁇ m are manufactured in the same order and conditions as in Comparative Example 2 except that a target obtained by sintering powder manufactured by incorporating 5 mol % of BaZrO 3 (BZO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used.
- BZO BaZrO 3
- a plurality of RE123-based superconducting wires in which the film thickness of the oxide superconducting layer has been changed in a range of 0.9 to 3.2 ⁇ m are manufactured in the same order and conditions as in Comparative Example 3 except that a target obtained by sintering powder manufactured by incorporating 7.5 mol % of BaSnO 3 (BSO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used.
- BSO BaSnO 3
- FIG. 8 illustrates the results in which the minimum values I cmin of the critical currents of the respective RE123-based superconducting wires are plotted.
- “BHO 3.5 mol %” represents the results of Example 4
- “PURE” represents the results of Comparative Example 6
- “BZO 5 mol %” represents the results of Comparative Example 7
- “BZO 7.5 mol %” represents the results of Comparative Example 8.
- RE123-based superconducting wires in which the film thickness of the oxide superconducting layer is 1 ⁇ m are manufactured in the same manner as in Example 4, and the critical current densities J c1 of the superconducting wires at 77 K in a 3T magnetic field are measured.
- J cd /J c1 is computed using the critical current density J cd of each of the superconducting wires of Example 4 at 77 K in a 3T magnetic field, which has been measured above, and the obtained J c1 .
- the critical current values are 70 A when the film thickness of the oxide superconducting layer is 5.2 ⁇ m; however, in the superconducting wires of Example 4 according to the present invention, the critical current values reach 85 A when the film thickness of the oxide superconducting layer is 2.9 ⁇ m. That is, it is found that a high critical current value can be realized in a thin oxide superconducting layer.
- the film thickness of the oxide superconducting layer in Example 4 is preferably in a range of 1 ⁇ m to 3 ⁇ m, but may be in a range of 1 ⁇ m to 5 ⁇ m.
- RE123-based superconducting wires are manufactured in the same order and conditions as in Example 1 except that a target obtained by sintering powder manufactured by incorporating 3.5 mol % of BaHfO 3 (BHO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 1.2 ⁇ m.
- a target obtained by sintering powder manufactured by incorporating 3.5 mol % of BaHfO 3 (BHO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 1.2 ⁇ m.
- RE123-based superconducting wires are manufactured in the same order and conditions as in Example 1 except that a target obtained by sintering powder manufactured by incorporating 3.5 mol % of BaHfO 3 (BHO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 2.2 ⁇ m.
- a target obtained by sintering powder manufactured by incorporating 3.5 mol % of BaHfO 3 (BHO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 2.2 ⁇ m.
- RE123-based superconducting wires are manufactured in the same order and conditions as in Comparative Example 2 except that a target obtained by sintering powder manufactured by incorporating 5 mol % of BaZrO 3 (BZO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 1.2 ⁇ m.
- a target obtained by sintering powder manufactured by incorporating 5 mol % of BaZrO 3 (BZO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 1.2 ⁇ m.
- RE123-based superconducting wires are manufactured in the same order and conditions as in Comparative Example 2 except that a target obtained by sintering powder manufactured by incorporating 5 mol % of BaZrO 3 (BZO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 2.6 ⁇ m.
- a target obtained by sintering powder manufactured by incorporating 5 mol % of BaZrO 3 (BZO) into powder of GdBa 2 Cu 3 O 7 ⁇ is used and the film thickness of the oxide superconducting layer is set to 2.6 ⁇ m.
- the critical current values linearly increase at a temperature in a range of 20 K to 77 K in a magnetic field in a range of 0 T to 5 T as the film thickness of the oxide superconducting layer increases.
- the same base material as the base material for superconducting wires used for the above superconducting wires is used as the base material for superconducting wires.
- a sintered body obtained by sintering powder of GdBa 2 Cu 3 O 7 ⁇ into which 5 mol % of BaZrO 3 has been incorporated is used as the target. Films are formed under conditions of a heater temperature of 1070° C., a pressure of 80 Pa, a laser output of 34 W and in an atmosphere with 100% oxygen.
- An oxide superconducting layer is formed while transporting the base material for superconducting wires at a transportation speed of 20 m/h using the PLD method in which the laser deposition apparatus illustrated in FIG. 2 is used.
- a long metallic base material is wound around the supply reel in the laser deposition apparatus illustrated in FIG. 2 as a dummy base material. An end portion of the long metallic base material is pulled out, fixed to the winding reel, and installed so that the long metallic base material can be transported in the longitudinal direction from the supply reel to the winding reel.
- the base material for superconducting wires manufactured above is connected to a supply reel side of the long metallic base material, which is the dummy base material installed between the pair of reels, in a manner that a film is to be formed on the CeO 2 layer.
- the supply reel and the winding reel are driven in synchronization with each other so as to transport the long metallic base material in the longitudinal direction and to transport the base material for superconducting wires which is fixed to the long metallic base material from the supply reel to the winding reel.
- An RE123-based oxide superconducting layer having a film thickness of 1.6 ⁇ m is formed on a CeO 2 layer while the base material for superconducting wires passes through a film-forming region opposite to a target.
- the base material is made to pass through the film-forming region multiple times with the repetitive change of transportation directions of the base material until the film thickness of the oxide superconducting layer reaches 1.6 ⁇ m.
- a 5 ⁇ m-thick Ag layer (stabilizing layer) is sputtered on the oxide superconducting layer, thereby manufacturing an RE123-based superconducting wire.
- the base material for superconducting wires is fixed and disposed so that a CeO 2 layer faces the target, and a 2 ⁇ m-thick RE123-based oxide superconducting layer is formed on the CeO 2 layer while the base material for superconducting wires is kept fixed without being transported.
- a 5 ⁇ m-thick Ag layer (stabilizing layer) is sputtered on the oxide superconducting layer, thereby manufacturing an RE123-based superconducting wire.
- FIG. 11 illustrates the results in which the minimum values I cmin of the critical currents of each of the RE123-based superconducting wires are plotted.
- the critical current values I cmin are 60 A when the film thickness of the oxide superconducting layer is 2 ⁇ m.
- the critical current values I cmin are 16.9 A when the film thickness of the oxide superconducting layer is 1.6 ⁇ m.
- the characteristic values of the fixed film formation which are obtained in the present examination example, are compared with a graph illustrated in FIG. 13 , it is found that, in the fixed film formation, the critical current increases in proportion with the film thickness even with the introduction of the BaZrO 3 artificial pinning centers when the film thickness increases from 1 to 2 ⁇ m as well.
- the increase in the critical current characteristics slows when the film thickness is increased.
- the characteristics of the superconducting wires illustrated in FIG. 13 are the superconducting characteristics of wires in which the oxide superconducting layer has been formed through the reel to reel film formation.
- the present invention is applied to an RE123-based superconducting wire including artificial pinning centers introduced into a superconducting layer and a method of manufacturing the same.
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CN103367626B (zh) * | 2013-07-02 | 2015-08-12 | 西北有色金属研究院 | 一种涂层导体超导膜及其制备方法 |
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WO2009044637A1 (ja) * | 2007-09-14 | 2009-04-09 | International Superconductivity Technology Center, The Juridical Foundation | Re123系酸化物超電導体とその製造方法 |
US7737087B2 (en) * | 2004-07-27 | 2010-06-15 | Los Alamos National Security, Llc | Enhanced pinning in YBCO films with BaZrO3 nanoparticles |
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JP3163122B2 (ja) * | 1991-07-30 | 2001-05-08 | 株式会社東芝 | 酸化物超電導体の製造方法 |
EP1481953A3 (de) * | 2003-02-19 | 2006-03-01 | Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden e.V. | Hochtemperatursupraleitender Körper und Verfahren zu dessen Herstellung |
JP2005054210A (ja) * | 2003-08-06 | 2005-03-03 | Fujikura Ltd | 薄膜の製造装置 |
JP4628041B2 (ja) * | 2004-08-25 | 2011-02-09 | 新日本製鐵株式会社 | 酸化物超電導材料及びその製造方法 |
JP5227722B2 (ja) * | 2008-09-30 | 2013-07-03 | 株式会社フジクラ | 多結晶薄膜とその製造方法及び酸化物超電導導体 |
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- 2012-06-29 WO PCT/JP2012/066701 patent/WO2013002372A1/ja active Application Filing
- 2012-06-29 CN CN201280029838.2A patent/CN103620702B/zh active Active
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US7737087B2 (en) * | 2004-07-27 | 2010-06-15 | Los Alamos National Security, Llc | Enhanced pinning in YBCO films with BaZrO3 nanoparticles |
JP2008130291A (ja) * | 2006-11-17 | 2008-06-05 | Central Res Inst Of Electric Power Ind | 超電導体膜及びその製造方法 |
WO2009044637A1 (ja) * | 2007-09-14 | 2009-04-09 | International Superconductivity Technology Center, The Juridical Foundation | Re123系酸化物超電導体とその製造方法 |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11107967B2 (en) * | 2018-10-16 | 2021-08-31 | Imam Abdulrahman Bin Faisal University | Yttrium-based superconductors with tungsten nano-structures |
US11770983B2 (en) | 2018-10-16 | 2023-09-26 | Imam Abdulrahman Bin Faisal University | Method for making Y123 superconducting material |
US12069968B2 (en) | 2018-10-16 | 2024-08-20 | Imam Abdulrahman Bin Faisal University | Solid state synthetic method for superconductor material |
US12089510B2 (en) | 2018-10-16 | 2024-09-10 | Imam Abdulrahman Bin Faisal University | Synthesis method for a YBCO superconducting material |
Also Published As
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EP2728589A4 (en) | 2015-04-15 |
KR20140037121A (ko) | 2014-03-26 |
JPWO2013002372A1 (ja) | 2015-02-23 |
EP2728589A1 (en) | 2014-05-07 |
CN103620702A (zh) | 2014-03-05 |
WO2013002372A1 (ja) | 2013-01-03 |
CN103620702B (zh) | 2016-08-17 |
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